package com.example.utils;

import org.springframework.stereotype.Component;
import javax.imageio.ImageIO;
import java.awt.image.BufferedImage;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.util.Random;
import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics;

/* *
 * @Author : 戢鹏
 * @Description ：kaptcha验证码
 * @Param ： * @param null
 * @Time : 2019/3/12 16:31
 * @Return 
 */

    @Component
    public class VerifyUtil {
        // 验证码字符集
        private static final char[] chars = {
                '0', '1', '2', '3', '4', '5', '6', '7', '8', '9',
                'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n',
                'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z',
                'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N',
                'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z'};
        // 字符数量
        private static final int SIZE = 4;
        // 干扰线数量
        private static final int LINES = 5;
        // 宽度
        private static final int WIDTH = 80;
        // 高度
        private static final int HEIGHT = 40;
        // 字体大小
        private static final int FONT_SIZE = 30;

        /**
         * 生成随机验证码及图片
         * Object[0]：验证码字符串；
         * Object[1]：验证码图片。
         */
        public static Object[] createImage() {
            StringBuffer sb = new StringBuffer();
            // 1.创建空白图片
            BufferedImage image = new BufferedImage(
                    WIDTH, HEIGHT, BufferedImage.TYPE_INT_RGB);
            // 2.获取图片画笔
            Graphics graphic = image.getGraphics();
            // 3.设置画笔颜色
            graphic.setColor(Color.LIGHT_GRAY);
            // 4.绘制矩形背景
            graphic.fillRect(0, 0, WIDTH, HEIGHT);
            // 5.画随机字符
            Random ran = new Random();
            for (int i = 0; i <SIZE; i++) {
                // 取随机字符索引
                int n = ran.nextInt(chars.length);
                // 设置随机颜色
                graphic.setColor(getRandomColor());
                // 设置字体大小
                graphic.setFont(new Font(
                        null, Font.BOLD + Font.ITALIC, FONT_SIZE));
                // 画字符
                graphic.drawString(
                        chars[n] + "", i * WIDTH / SIZE, HEIGHT*2/3);
                // 记录字符
                sb.append(chars[n]);
            }
            // 6.画干扰线
            for (int i = 0; i < LINES; i++) {
                // 设置随机颜色
                graphic.setColor(getRandomColor());
                // 随机画线
                graphic.drawLine(ran.nextInt(WIDTH), ran.nextInt(HEIGHT),
                        ran.nextInt(WIDTH), ran.nextInt(HEIGHT));
            }
            // 7.返回验证码和图片
            return new Object[]{sb.toString(), image};
        }

        /**
         * 随机取色
         */
        public static Color getRandomColor() {
            Random ran = new Random();
            Color color = new Color(ran.nextInt(256),
                    ran.nextInt(256), ran.nextInt(256));
            return color;
        }

        /*生成验证码图片 测试*/
        public static void main(String[] args) throws IOException {
            Object[] objs = createImage();
            BufferedImage image = (BufferedImage) objs[1];
            OutputStream os = new FileOutputStream("d:/1.png");
            ImageIO.write(image, "png", os);
            os.close();
        }
    }

